Centralized lubricating system



NOV. 27, 1934. i O u ZERK 1,982,093

CENTRALIZED LUBRIGATING SYSTEM Filed Sept. 21, 1929 17 Sheets-Sheet 1Nov. 27, 1934. o. u. ZERK 7 CENTRALIZED LUBRICATING SYSTEM 17Sheets-Sheet 2 Filed Sept. 21, 1929 Nov. 27, 1934.

0. U. ZERK CENTRALIZED LUBRIGATING SYSTEM Filed Sept. 21, 1929 17Sheets-Sheet 5 Nov. 27, 1934. o. u. ZERK CENTRALIZED LUBRICATING SYSTEMFiled Sept. 21, 1929 17 Sheets-Sheet 5 Nov. 27, 1934. o. u. ZERK1,982,093

CENTRALIZED LUBRICATING SYSTEM Filed Sept. 21', 1929 17 Sheets-Sheet 6Nov. 27, 1934. o. u. ZERK CENTRALIZED LUBRICATING SYSTEM Filed Sept. 21,1929 1.7 Sheets-Sheet 9 Nov. 27, 1934. I o, u ZERK 1,982,093

CENTRALIZED LUBRICATING SYSTEM Filed Sept. 21, 1929 17 Sheets-Sheet l0 5Jaws Nov. 27, 1934. o. u. ZERK CENTRALIZED LUBRICATING SYSTEM FiledSept. 21, 1929 l7 Sheets-Sheet ll lodvn r Ma- Nov. 27, 1934. o. u. ZERKCENTRALIZED LUBRICATING SYSTEM Filed Sept; 21, '1929 17 Sheets-Sheet 124. J WI I 1. H

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Nov. 27, 1934. ofu. ZERK CENTRALIZED LUBRICATING SYSTEM Filed. Sept. 21,1929 17 Sheets-Sheet l4 NOV. 27, O. U. ZERK 179822093 CENTRALIZEDLUBRICATING SYSTEM I Filed Sept. 21, 1929 1.7 Sheets-Sheet 16 7! I II!!!/24;z

I ll I 267 275 Patented Nov. 27, 1934 UNITED STATES PATENT OFFICECENTRALIZED LUBRICATING SYSTEM Application September 21, 1929, SerialNo. 394,363

40 Claims.

My invention relates to centralized lubrication and while it isparticularly applicable to automotive work, more particularly to thelubrication of the chassis of vehicles, such as automobiles, tractors,gun carriages, war tanks, locomotives, aeroplanes and the like, it isalso adaptable to industrial lubrication, that is to the lubrication ofstationary machines, such as stamping presses, printing presses, textilemachinery, shafting and the various types of machines and machine toolsemployed in modern industry.

Heretofore centralized chassis lubrication has employed oil. While oilis a good lubricant, it cannot be employed successfully for certainbearings of an automobile, such as the wheel spindles and the like wherecavities adjacent the bearings must be filled and from which cavities itis customary to have the bearings derive their supply of lubricant. Inmany places such cavities are covered with leather or the like andcannot be made entirely leakproof. There are numerous other places inthe chassis of an automobile and the like such as king bolt bearings,particularly where ball or roller bearings are employed, tie rodbearings, steering knuckle bearings, front wheel brake bearings,steering gear housing bearings, and the like, where such cavities arecustomarily provided. Due to the fact that grease is the best lubricantfor these cavity surrounded bearings they have heretofore been designedfor grease lubrication and even in those machines where a centralizedsystem of chassis lubrication using a thin grade of oil is provided forthe rest of the bearings, a separate hand-operated grease gun system isemployed for such cavity surrounded bearings.

In such systems where there are from ten to fifteen chassis bearingsdepending upon grease lubrication by the use of a hand gun or the like,the operator is likely to depend upon the centralized lubricating systemand to either overlook the grease lubricated bearings or he may gain theimpression that the centralized chassis lubricating system takes care ofall of the bearings of the car. The result is often a complete failureto lubricate the grease lubricated bearings.

The chief advantage in using grease instead of oil in centralizedchassis lubrication is that grease will stay in place while oil flows.Hence grease does not drip from the bearings or from the pipe linesystem. Oil on the other hand tends to drip from the bearings or fromthe pipe line system and form pools of oil below the car which is highlyundesirable. The use of grease also makes it possible to do away withcheck valves in metering units, particularly in resistance units.

However, with the great advantages which are possible with the use ofgrease for a centralized system of chassis lubrication, I find thatgrease has not heretofore been successfully used for centralized chassislubrication. In large part this appears to be due to the difliculty ofmoving the grease through the inside of a relatively long pipe line. Dueto the resistance of the pipe line there would be a relatively greatvariation in resistance to flow of the grease as between a bearingnearest the grease pump and a bearing remote therefrom, with the resultthat there would be a tendency for the grease to escape from the nearestoutlet and very little would pass to the remote bearing.

Automatic systems for pumping oil into the pipe line system and into thebearings are known, and in these the pump delivers very small dischargesof oil.

If air should become entrained in the oil it would tend to separate outby gravity, whereas if air becomes entrained in the grease, and this isnot at all unusual, the extremely small displacement of the pump whichis employed to pump the grease is rendered inefiective by the presenceof such a bubble of air since the same cannot disentrain itself fromgrease. After such a bubble of air gets into the pump it is diflicult todislodge the same and until it is dislodged grease willnot be drawn intothe pump with the result that the entry of air into a very smalldisplacement pump for grease will render such system inoperative.

The principal object of the present invention is to provide acentralized lubricating system, utilizing grease or very high viscosityoil for lubricating an automobile chassis'or any other machine ormachine tool. The system herein shown is particularly designed for theuse of grease but is equally applicable to the employment of a highviscosity oil.

In considering a suitable mode for the employment of grease in acentralized lubricating system, there are a number of importantconsiderations and requirements to be met.

It is undesirable to force the grease serially to the various bearingsthrough a small, highresistance, pipe line system, because ofthe'friction to flow which is thereby presented.

It is an aim of my invention to avoid this difiiculty, primarily byemploying relatively large diameter tubing and to make the distributionas nearly equal as is possible within structural limitations andcommercial practice, from the grease pump to the various bearings. Inthe preferred construction I secure this result by employing amanifolded delivery connection, for example, by delivering grease fromthe pump to a pipe line on each side of the chassis frame at a pointintermediate the front and rear end of each side.

Another feature of my invention is to employ the free running greasedisclosed in my copending application Serial No. 384,120, filed August7, 1929. Another feature in reducing'the friction of fiow is to preparethe inside surface of the pipe line system to decrease the flowresistance, either in connection with the specially prepared grease orin connection with such grease as is known.

Another consideration in a system of this character is the desirabilityfor positive displacement of a definite quantity of grease periodically.That is to say it is possible to distribute grease to the variousbearings by forcing into the pipe line system minute amountssuccessively, but I consider it preferable to deliver periodically adefinite relatively large charge of grease which will distribute itselfto the various bearings as predetermined.

This positive discharge movement. should be made relatively rapid andwith sufficient power available to secure the desired movement of thegrease.

In considering the means for obtaining such intermittent measureddischarges of grease, it is of course possible to employ gearing betweensome moving parts and a final plunger which will deliver the grease butsuch a construction is subject to certain disadvantages, both because ofcost and the necessary mechanical complications which are involved.Also, a slow movement of the final piston is highly undesirable sincethe purpose of the same might be completely defeated by a small leakagepast the same. 1

I consider it advisable to have a definite rapid motion which is muchless affected by leakage and which has a tendency to gain betterdistribution in the pipe line system.

The specific means herein disclosed involves the use of a smalldisplacement air pump which successively discharges small volumes of airinto an accumulating chamber which will be charged with compressed airat a value suitable for performing the discharge or displacementoperation and when such accumulated volume of compressed air has beencollected it is released from the accumulating chamberand applied to thework of displacing the lubricant into the pipelin system and to thebearings.

While the preferred means for compressing the air is a small compressoroperated from the variations of fiuid pressure in the shock absorber ofthe vehicle, it will be apparent that within the teaching of my presentinvention .the air may be accumulated from any suitable source and theaccumulated charge applied to the work of displacing the lubricantperiodically.

In the distribution of the grease to the various bearings, I havedeveloped two general modes of distribution. One is to employ cavitiesin conjunction with the hearings to be greased or lubricated, theoutlets of the bearings being restricted so as to facilitate theretention of grease in such cavities. The second method of distributionis to insert resistance units of predetermined character in advance ofsuch cavities so as to equalize substantially the pressure within thepipe line system and to secure equal emission at the various meteringunits where equal emission is desired into thecavities. In brief, Iprovide the resistance either in advance of the cavity or where from thenature of the bearing it is advisable to do so I place the resistance atthe remote end of the bearing.

In further explanation of the above general methods, I shall hereafterpoint out refinements of the said methods of attaining distribution ofthe grease to the various bearings of the automobile or the like underthe above two general schemes. Sufiice it here to say that as a specialor particular case of bearings having cavities or passagewaysofrelatively large size with relatively free inlets, I may transmitlubricant through such cavities or passageways in series to otherbearings whether the latter have restricted inlets or outlets.

In connection with bearings fed by grease or high viscosity oil throughrestricted inlets, that is with distribution resistances on the inletside, my present invention provides certain highly importantimprovements. I have conceived the desirability of making the resistancepassageways of such size that particles of dirt and the like will notclog up the same. To get suflicient resistance to make the resistance ofthe nearest outlet equal to a tight bearing at a remote point would,however, require an unduly long passageway and undesirably highresistance. Therefore, according to my present invention I reduce thevresistance of the bearings to an extent that will make them less thanthat of a resistance plug of reasonable dimensions and'relatively lowresistance but having a passageway large enough to pass such particlesof dirt as are commonly encountered in grease. This will be morespecifically pointed out in the following objects, detailed descriptionand in the claims.

In the developmentof a system and particularly an automatic system forutilizing grease as a lubricant throughout for chassis lubrication orthe like, I have been forced to develop and provide improvements indetail extending to substantially all of the units and features of sucha system, all of which will be more specifically pointed out in thefollowing detailed specification and claims and to which I shall callattention generbe more fully set forth in detail and claimed here--after.

An object of this invention is to transform a large number of motions oroperations incident to the operation of a vehicle into a single motionor operation for securing a periodic action of a device in connectionwith centralized lubrication or the lke.

Another object is to accumulate a charge of compressed gas by a largenumber of separate compressing operations and to utilize this charge toperform a single operation, such as discharging grease into a pipe line.I may thereby reduce a large number of positive motions into a singlerapid motion which is preferably impositive but may be made relativelypositive by suitable design.

Another object of the invention is to compress air and irrespective ofthe amount of air com-- pressed to press yieldingly a predeterminedamount of grease or oil into the pipe line system leading to thebearings to be lubricated.

Another object of the invention is to compress air and after apredetermined amount of air has been compressed to employ such volume ofcompressed air to discharge a predetermined amount of grease or oil,such amount of grease or oil being entirely independent of the volume ofair which is compressed.

Another object of the invention is to use any kind of automatic air pumpwith air pressure reservoir and with automatically opening outlet valveto operate when the pressure in the air reservoir has reached apredetermined quantity or pressure. Such automatically operated airpumps may consist of:

1. An air pump hydraulically connected to a hydraulic shock absorber.

2. An air pump mechanically connected to a hydraulic shock absorber orthe like.

3. An inertia operated pump.

4. A pneumatically operated air pump.

5. An air pump driven from the speedometer shaft or from any revolvingor moving part of the automobile.

Another object of the invention is to use any of the above named pumpswith means for filtering the air and to employ means whereby thecondensed water in the pump or oil reservoir due to humid atmospherecannot enter the lubricant pump, nor clog nor freeze up any conduit orvalve mechanism of the air pump.

Another object of the invention is to let the condensed water accumulatein the air compres sion chamber or reservoir without interfering withthe action of the air. pump.

Another object of the invention is to derive the power for operating theentire lubricating system from a fluid shock absorber, preferably of thehydraulic type.

Another object of my invention is to prevent any leakage of the shockabsorber fluid when operating the air pump.

Another object of my invention is to connect the air pump to the shockabsorber in such a manner that it will not interfere with the relativemovements of axle and frame of the automobile, nor any of the otherfunctions of the automobile.

Another object of the invention is to employ a type of 'air pump whichwill utilize only the beginning of the shock absorber movement, thusmaking the stroke of the air compressing pump independent of theamplitude of movement of the body relative to the axle, that isindependent of the size of the bumps in the road.

Another object of the invention is to obtain substantiallyequal'movements of the small air pump piston independently of the lengthor size of the shock to which the car is subjected.

Another object of the invention is to use only one of the two oppositemotions of the hydraulic shock absorber in operating the air pump.

Another object of the invention is to provide a diaphragm for operatingthe piston of the air pump, this diaphragm being subject to the fluidpressure in the fluid shock absorber.

Another object of the invention is to move the piston of the air pumpforward by one operation of the hydraulic shock absorber and backward bythe opposite action of the shock absorber, thus eliminating springs.

Another object of the invention is to filter the air leading to thepiston inlet and the air leading to the front portion of the diaphragmthrough the same air cleaner preferably attached to the air pump.

Another object of the invention is to connect the air conduit leading tothe piston inlet and the front portion of. the diaphragm to any sourceof clean air, as for example within the air cleaner which purifies theair leading to the carburetor.

Another object of the invention is to employ a transparent glassreservoir as a grease container:

Another object of the invention is to provide a follower in thetransparent glass reservoir. This follower is arranged to be quicklyinterchanged if necessary.

Another object is to provide a glass reservoir which may be either offour forms, viz. 1, bottom supported in center; 2, bottom supported atcircumference; 3, top suspended; 4, side supported.

Another object of my invention is to provide an air operated piston,preferably of the differential type in the grease pump.

Another object of theinvention is to prov-:lmeans whereby the air backof the air piston in the air operated grease pump will be reduced tosubstantially atmospheric pressure after the piston of the air operatedgrease pump has reached the end of its forward stroke. This object I mayaccomplish in any of the following ways. 1, by means of a plain airbleeder; 2, by means of an air bleeder using high viscosity zero oil; 3,by means of a snap valve mechanically actuated by the movement of thepiston.

Another object of my invention is to close the outlet from the greasereservoir to the grease pump when the grease reservoir is substantiallyempty and the grease follower has reached the end of its movement. Whenthe outlet is thus shut off the pump creates a partial vacuum instead ofdrawing air from the empty grease reservoir and injecting the same intothe pipe line system.

Another object of the invention is to make the glass reservoirquickly'detachable in case it is desired to refill the same with greaseas by means of a paddle.

Another object of my invention is to supply means whereby the glassreservoir may be filled with grease without detaching the same from theautomobile. This is preferably secured by providing a quick detachableand attachable means to connect a large grease container with the glassreservoir so that the reservoir may be filled from the large greasecontainer.

Another object of the invention is in'conjunction with the reservoirfilling means to provide an automatic grease escape valve to preventbursting of the glass'reservoir or the passing of grease above the topof the follower when the glass reservoir is filled with grease.

Another object of the invention is to provide cavities adjacent thebearings, which cavities are filled with lubricant from the lubricantpump, these cavities taking the place of metering units.

Another object of the invention is to secure equalization of pressure inthe distributing system by creating resistance at the end of each suchcavity.

Another object of my invention is to employ as an alternative aresistance unit having a channel so large that the dirt or grit in thegrease can pass through the channel without clogging the same, thuseliminating the use of screens.

Another object of the invention is to provide a construction of meteringunit in which the resistance plug is quickly interchangeable withoutdetaching the body of the resistance unit or the pipe

